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Biomedical subjects

Y Hatano

Publications and source records attributed to Y Hatano.

At least 73 records · Page 4Linked to original sources
PubMed1997

Translocation (8;12;21)(q22.1;q24.1;q22.1): a new masked type of t(8;21)(q22;q22) in a patient with acute myeloid leukemia.

The translocation t(8;21)(q22;q22) is found in 40% of cases of acute myeloid leukemia (AML) designated as the subtype M2 in the French-American-British (FAB) classification. The 8;21 translocation is clinically of interest because patients with this subtype have a good prognosis. We describe a masked type of the translocation, t(8;12;21)(q22.1;q24.1;q22.1). The translocation was first interpreted as t(8;12)(q22;q24) based on cytogenetics, but was reevaluated as a result of Southern blot and fluorescence in situ hybridization (FISH) analyses.

Acute Disease↗
PubMed1997

Decreased expression of cytokines that induce type 1 helper T cell/interferon-gamma responses in genetically susceptible mice infected with Mycobacterium avium.

Mycobacterium avium is an intracellular microorganism that infects and multiplies within macrophages. Cell-mediated immunity plays an important role in host defense. Two cytokines, interleukin 12 (IL-12) and interferon-gamma-inducing factor (IGIF), produced mainly by macrophages, are critical for the development of type 1 helper T (Th1) cell/interferon-gamma (IFN-gamma) responses and cell-mediated immunity. In this report, by using a mouse model of disseminated M. avium infection, we demonstrate that genetically susceptible BALB/c mice show decreased expression of IL-12 and IGIF in association with a diminished IFN-gamma/Th1 response. Conversely, resistant DBA/2 mice exhibited increased expression of IL-12, IGIF, and IFN-gamma. In both strains of infected mice, the level of IL-4/Th2 response was similar. These results suggest that decreased expression of IL-12 and IGIF leads to a diminished Th1 response without reciprocal enhanced Th2 responses in susceptible mice.

Animals↗
PubMed1997

Platelet aggregation is impaired during anaesthesia with sevoflurane but not with isoflurane.

PURPOSE: Halothane suppresses platelet aggregation in vitro and ex vivo, and prolongs bleeding time. In a previous in vitro study we demonstrated that sevoflurane had a more suppressive effect on platelet aggregation than did halothane. The present study investigated whether the clinical use of sevoflurane affected platelet aggregation ex vivo. METHODS: Thirty-eight patients undergoing minor elective surgery were divided randomly into sevoflurane and isoflurane groups. Anaesthesia was induced with thiopentone i.v., and was maintained with sevoflurane or isoflurane with nitrous oxide. Blood was collected to measure platelet aggregation induced by adenosine diphosphate (ADP) and epinephrine. The first (control) blood collection was performed in the operating room before induction of anaesthesia, and the second 5-10 min after tracheal intubation but before the start of surgery, when the end-expiratory sevoflurane or isoflurane concentrations had stabilised at 1-1.5 times the minimum alveolar concentration (MAC) and mean arterial pressures were between 80-120% of preanaesthetic values. RESULTS: In all samples obtained during sevoflurane anaesthesia (n = 15), ADP and epinephrine could not induce secondary aggregation, although they did induce primary aggregation. In contrast, in the isoflurane group, both primary and secondary aggregation were observed in 14 out of 15 patients, and secondary aggregation was abolished in only one of the samples obtained during anaesthesia. CONCLUSIONS: Sevoflurane, but not isoflurane, alters platelet aggregation in the clinical situation, possibly by suppression of thromboxane A2 formation.

Adult↗
PubMed1997

Halothane inhibition of acetylcholine-induced relaxation in rat mesenteric artery and aorta.

PURPOSE: The effect of halothane was compared on acetylcholine (ACh)-induced relaxation of the mesenteric artery and the aorta in rats. METHODS: The responses of isolated rat aortic and mesenteric arterial ring segments precontracted with phenylephrine to ACh (10(-8)-10(-5) M), in the presence of halothane 0-3%, were compared using isometric force tension recordings. Effects of NG-nitro-l-arginine (L-NOARG, 3 x 10(-5), methylene blue (MB, 5 x 10(-6) M), oxyhaemoglobin in (OxyHB, 10(-7) M), and various potassium channel inhibitors; tetraethylammonium (TEA, 10(-5) M, 10(-3) M), apamin (AP, 10(-7) M), charybdotoxin (ChTx, 10(-7) M) and glibenclamide (GC, 10(-5) M) on ACh-induced relaxation in mesenteric artery were tested. Using radioimmunoassay, ACh (10(-6) M)-induced guanosine 3':5'-cyclic monophosphate (cGMP) accumulation of mesenteric arterial rings pretreated with L-NAORG were also measured. RESULTS: L-NOARG partially inhibited ACh-induced relaxation in mesenteric arterial rings (P < 0.05, maximum relaxation reduced by approximately 50%), whereas it abolished them in aortic rings. The remaining relaxation resistant to L-NOARG in mesenteric arterial rings was insensitive to additional MB or OxyHB, and was not accompanied by increases in cGMP contents of rings. Halothane inhibited endothelium-dependent relaxation in aorta and mesenteric arterial rings. This inhibitory effect was larger in aorta. Halothane also inhibited NO independent EDHF-dependent relaxation in the mesenteric arterial rings, CONCLUSION: Despite a similar inhibitory effect on the EDHF relaxing pathway, halothane has a larger effect on endothelium-dependent relaxation in the aorta (NO dependent mainly) than in the mesenteric rings (NO and EDHF dependent).

Acetylcholine↗
PubMed1997

Volatile anaesthetics attenuate hypocapnia-induced constriction in isolated dog cerebral arteries.

PURPOSE: Hypocapnia causes cerebral arterial constriction, whereas volatile anaesthetics cause dilatation. The purpose of this study was to compare the direct effects of halothane, isoflurane and sevoflurane on hypocapnia-induced constriction of isolated cerebral arteries in vitro. METHODS: Basilar and middle cerebral arteries of mongrel dogs (n = 11) were cut into rings and mounted for isometric tension recording in organ baths containing Krebs' bicarbonate solution, aerated with CO2 5% and O2 95% at 37 degrees C. After constriction with 20 mM KCl, hypocapnia was induced by replacing the aerating gas with CO2 2.5% and O2 97.5% in the presence or absence of anaesthetics. RESULTS: Exposure of cerebroarterial rings to the hypocapnic gas produced sustained vasoconstriction (418 +/- 19 mg), reaching a plateau within 10 to 15 min. Halothane (0.5, 1, 2 MAC) attenuated the hypocapnia-induced constriction (P < 0.05). In contrast, isoflurane and sevoflurane attenuated this constriction only at 2 MAC (P < 0.05). Attenuation by halothane was greater than that by isoflurane or sevoflurane at each concentration (P < 0.05). NG-nitro-L-arginine (3 x 10(-5) M) did not alter the contractile response to hypocapnia. When a similar degree of constriction was induced by addition of 10 mM KCl, halothane (1 and 2 MAC) preferentially attenuated the constriction induced by hypocapnia to a greater extent than that induced by 10 mM KCl (P < 0.01). CONCLUSION: Hypocapnia-induced vasoconstriction of isolated dog cerebral arteries precontracted with KCl is more susceptible to halothane than isoflurane or sevoflurane. This may account for the greater increase in cerebral blood flow during halothane than isoflurane or sevoflurane anaesthesia.

Anesthetics, Inhalation↗
PubMed1997

Cerebellar myeloblastoma formation in CD7-positive, neural cell adhesion molecule (CD56)-positive acute myelogenous leukemia (M1).

We present a first report of a CD7+ acute myelogenous leukemia patient who developed intracranial myeloblastomas. The patient was neurologically normal on physical examination at presentation. The peripheral leukocyte count was extremely high (203.6 x 10(9)/l). The blasts expressed CD7 and CD56 (neural cell adhesion molecule) in addition to CD13, CD33, CD34, and HLA-DR. The karyotype of bone marrow cells was normal. The patient was diagnosed as having acute myelogenous leukemia (AML, M1). Following a short period of complete remission, bone marrow relapse and meningeal leukemia occurred, and the patient died of respiratory failure. Autopsy revealed that blasts had invaded the subarachnoid space and cerebellum, and two myeloblastomas were found in the cerebellar hemisphere. Both CD7+ and CD56+ AML have been reported to have a high incidence of central nervous system involvement. CD7+ CD56+ AML calls for prophylaxis of central nervous system leukemia.

Antigens, CD7↗
PubMed1997

Increased levels of IL-13 mRNA, but not IL-4 mRNA, are found in vivo in peripheral blood mononuclear cells (PBMC) of patients with atopic dermatitis (AD).

Previous studies using in vitro systems with various stimuli have shown that PBMC from patients with AD show increased levels of IL-4 but decreased levels of interferon-gamma (IFN-gamma) compared with PBMC from normal controls. However, in vitro conditions do not always mimic the in vivo condition. We therefore believe that it is important to quantify the expression of these cytokines in freshly isolated PBMC. This study examines the expression of IFN-gamma, IL-4 and IL- 13 mRNA in freshly isolated PBMC from adult patients with AD, from patients with psoriasis vulgaris and from healthy adults, using the semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) method. Levels of IFN-gamma mRNA were significantly lower in PBMC of patients with AD than in controls. IL-4 mRNA levels did not differ significantly between groups. Conversely, levels of mRNA for IL-13 were significantly greater in PBMC of patients with AD than in controls. An increase in IL-13 expression may regulate the in vivo synthesis of IgE in patients with AD.

Adolescent↗
PubMed1997

Displacement of the double-lumen endobronchial tube can be detected by bronchial cuff pressure change.

We measured the bronchial cuff pressure of left-sided double-lumen endobronchial tubes (DLTs) in 54 patients to confirm the effect of DLT displacement on cuff pressure. After positioning the cephalad surface of the bronchial cuff of the DLT 2.5 cm distal to the carina (23 patients in the first part of the study) or just below the carina (23 patients in the second part), the cuff was withdrawn in 0.5-cm steps during right-sided, one-lung ventilation. The bronchial cuff pressure was measured, and the capnogram and pressure-volume loop, displayed by a side-stream spirometer, was evaluated. After positioning the cephalad surface of the bronchial cuff just below the carina (eight patients in the third part), bronchial cuff pressure was measured while confirming the position of the bronchial cuff during the 30 min of the operative procedure. The bronchial cuff pressure decreased significantly by 28.4 cm H2O (P < 0.01) and 21.3 cm H2O (P < 0.01) in the first and second parts, respectively, before the pressure-volume loop or the capnogram changed. The bronchial cuff pressure in the third part showed no significant change. We conclude that bronchial cuff pressure monitoring was very helpful in detecting displacement of the DLT during right-sided, one-lung ventilation.

Adult↗
PubMed1997

Different effects of halothane, isoflurane and sevoflurane on sarcoplasmic reticulum of vascular smooth muscle in dog mesenteric artery.

BACKGROUND: The direct effect of halothane on vascular smooth muscle is mediated in part via its effects on the sarcoplasmic reticulum (SR). Little information is available concerning the effects of other volatile anesthetics including isoflurane and sevoflurane, whose vascular effects differ from those of halothane. The aim of the present study was to compare the effects of halothane, isoflurane and sevoflurane on the SR by testing the contraction induced by caffeine in vascular smooth muscle. METHODS: Rings without endothelium from isolated canine mesenteric artery were mounted in physiological saline solution (PSS) for isometric tension recording. After complete depletion of Ca2+ from the SR by adding 35 mM caffeine, the rings were exposed to normal Ca2+ containing PSS (Ca2+ loading), to Ca(2+)-free PSS for 10 min, and then to 15 mM caffeine to induce contraction. Anesthetics were administered during Ca2+ loading, the Ca(2+)-free phase and simultaneously with caffeine administration. RESULTS: Halothane (0.5-2%) attenuated the caffeine-induced contraction of canine mesenteric artery when administered during Ca2+ loading in the SR (P < 0.001), whereas isoflurane and sevoflurane (1-4%) failed to affect the contraction. When given simultaneously with caffeine, halothane (1-2%) potentiated the caffeine-induced contraction (P < 0.05), but isoflurane and sevoflurane had no effect. When given before caffeine administration, halothane (0.5-2%), isoflurane (2-4%) and sevoflurane (4%) all potentiated the caffeine-induced contraction (P < 0.05). CONCLUSION: It has been shown that halothane not only potentiates caffeine-induced Ca2+ release from the SR, but also induces contraction by releasing Ca2+ from the SR. We conclude that halothane decreases Ca2+ accumulation in the SR while exerting facilitative and additive effects on caffeine-induced Ca2+ release from the SR when applied before caffeine administration and simultaneously with caffeine, respectively, whereas isoflurane and sevoflurane lack both the ability to decrease Ca2+ accumulation and an additive effect on caffeine-induced Ca2+ release from the SR, but are able to facilitate Ca2+ release by caffeine.

Anesthetics, Inhalation↗
PubMed1997

Suppression of acetylcholine-induced relaxation by local anesthetics and vascular NO-cyclic GMP system.

BACKGROUND: Local anesthetics have been demonstrated to attenuate acetylcholine-induced relaxation of vascular smooth muscle, but the mechanism responsible has not been elucidated. The present study was undertaken to ascertain whether this effect of local anesthetics is due to suppression of the vascular nitric oxide (NO)-cyclic GMP (cGMP) system. METHODS: Isolated rat aortae were cut into helical strips and mounted in bathing solution to measure isometric tension changes. They were precontracted with phenylephrine (0.3 microM) then exposed to cumulative concentrations of relaxants including acetylcholine, sodium nitroprusside (SNP) and papaverine, in the absence or presence of local anesthetics. Aortae for cGMP measurements were cut longitudinally into pairs of strips and bathed in the solution without tension. In the absence or presence of anesthetics, they were stimulated with acetylcholine or SNP, and the cGMP content of each strip was radioimmunoassayed. RESULTS: Acetylcholine-induced, endothelium-dependent relaxation of phenylephrine-precontracted aortae was attenuated by lidocaine (30-300 microM), tetracaine (10-30 microM), bupivacaine (10-100 microM) and ropivacaine (30-100 microM). SNP-induced relaxation was attenuated by lidocaine (300 microM), tetracaine (30 microM), bupivacaine (10-100 microM) and ropivacaine (30-100 microM). Papaverine-induced relaxation was attenuated by lidocaine (300 microM), bupivacaine (30-100 microM) and ropivacaine (30-100 microM), and augmented by tetracaine (30 microM). Cyclic GMP levels in acetylcholine-stimulated aortae were reduced significantly by lidocaine (300 microM), tetracaine (100 microM) and bupivacaine (300 microM) treatment, but not by ropivacaine (300 microM). SNP-stimulated cGMP levels were reduced by tetracaine (100 microM) but not by any other anesthetics at the concentrations tested. CONCLUSION: We conclude that lidocaine, tetracaine and bupivacaine suppress acetylcholine-stimulated formation of cGMP. However, the attenuation of acetylcholine-induced relaxation by local anesthetics is not totally ascribable to reduced cGMP levels.

Acetylcholine↗
PubMed1997

[Antiemetic efficacy of granisetron in repeated CAF chemotherapy after breast cancer operation].

The antiemetic efficacy of granisetron in repeated CAF chemotherapy after breast cancer operation was investigated. Twenty-three patients who were treated with repeated CAF chemotherapy after breast cancer operation received drip-infused granisetron (3 mg/body) to prevent nausea and vomiting. Antiemetic efficacy was evaluated by means of the severity of nausea and the frequency of vomiting. The antiemetic efficacy rate of the drug was 74.4%. However, the average rate of antiemetic efficacy was 86.9% on the first through the sixth administration of the chemotherapy (first period). 75.9% on the seventh through the twelfth (second period), 48.4% on the thirteenth through the eighteenth (third period), and 31.8% on the nineteenth through the twenty-fourth (fourth period). There were significant differences in the antiemetic efficacy rate among the first, second and third periods. The antiemetic efficacy of granisetron decreased significantly by repeated CAF chemotherapy.

Adult↗
PubMed1997

In vivo expression of IL-4, IL-5, IL-13 and IFN-gamma mRNAs in peripheral blood mononuclear cells and effect of cyclosporin A in a patient with Kimura's disease.

Semiquantitative reverse transcription-polymerase chain reaction was used to analyse the expression of cytokine mRNAs in freshly isolated peripheral blood mononuclear cells obtained from a patient with Kimura's disease. The patient was treated with cyclosporin A (CsA) after incomplete tumour resection and irradiation of lesions. Levels of interleukin (IL)-4, IL-5 and IL-13 mRNA were elevated and the level of interferon (IFN)-gamma mRNA was within normal limits before treatment. The levels of IL-4, IL-5 and IL-13 mRNA, the number of eosinophils, and the serum level of IgE decreased markedly after surgery and radiation therapy. CsA treatment suppressed these values in a dose-dependent manner, but had a minimal effect on the level of IFN-gamma mRNA. The number of peripheral eosinophils decreased in association with decreases in the levels of IL-4, IL-5 and IL-13 mRNAs during CsA therapy; the serum level of IgE remained low during therapy and did not fluctuate in association with changes in cytokine levels. These results suggest the Th2 cytokines play a part in the development of Kimura's disease and that CsA suppresses the activity of this disease.

Aged↗
PubMed1996

Adenomyoepithelioma of the Breast: A Case Reprot and a Review of Literature.

A 74-year-old woman complained of a small nodule in the outer lower quadrant of her left breast. On physical examination, a 0.9 x 0.8 cm, round-shaped and firmly elastic nodule was palpated. Excisional biopsy was performed. Histologically, the tumor was separated into, with a bicellular pattern, containing both numerous glandular structures and numerous spindle-shaped cells. Immunohistochemical staining for EMA and cytokeratin showed strongly positive immunoreactivity for epithelial cells. Staining for &aipha;-SMA showed strongly positive immunoreactivity for myoepithelial components. Staining for keratin and S-100 protein showed weakly positive immunoreactivity for myoepithelial cells. Microscopically, the tumor was diagnosed as adenomyoepithelioma of the breast. Immunohistochemical examination is needed to distinguish epithelial cell proliferation from myoepithelial cell proliferation. Immunohistochemical examination using antibodies against EMA, alpha-SMA, Keratin, cytokeratin and S-100 protein, is indispensable.

Journal Article↗
PubMed1996

Translocation (9;11;22)(p22;q23;q11). A new type of complex variant translocation of t(9;11)(p22;q23) with MLL rearrangement.

We describe a patient with acute monocytic leukemia (M5a, FAB classification) associated with a new type of variant translocation (9;11). Southern blot analysis showed the rearrangement of the MLL (ALL-1/HRX) gene at 11q23. Fluorescence in situ hybridization (FISH) with painting probes of chromosomes 9, 11, and 22 revealed the translocation as t(9;11;22) (p22;q23;q11). This is more evidence that the production of chimeric mRNA following the translocation of the LTG9 (MLLT3/AF9) gene at 9p22 to 11q is a critical event in this leukemia subtype.

Adult↗
PubMed1996

Electron microscopic observations of aberrant capsids of pseudorabies virus.

Interactions between four strains of pseudorabies virus (PrV) and seven kinds of cell lines were examined. Three kinds of cells (SKL, CPK and PK-15) were especially infected with PrV at an MOI of about 10 PFC/cell. At sequential intervals after infection, cells of these types were collected for electron microscopic observations and the infectious doses of culture fluids were assayed. Developmental features of PrV were found to be very similar to those of herpes simplex virus (HSV), with the slight difference that PrV developed a little earlier and more vigorously than did HSV. At the late stage of infection, aberrant capsids of PrV were observed frequently in the nucleus of SKL but rarely in the nuclei of CPK and PK-15. The titer of infectious virus produced by SKL was much larger than that produced by CPK and PK-15. Immuno-electron microscopic examination using a monoclonal antibody against the major capsid protein of PrV clearly demonstrated that the complete and aberrant capsids have a common epitope. The mechanism of the formation of aberrant capsids is discussed.

Animals↗
PubMed1996

A beta-adrenoceptor agonist evokes a nitric oxide-cGMP relaxation mechanism modulated by adenylyl cyclase in rat aorta. Halothane does not inhibit this mechanism.

BACKGROUND: The objective of this study was to characterize the effects of halothane on the agonist-induced nitric oxide-cyclic GMP (NO-cGMP) mechanisms by comparing the intracellular signal transduction mediating isoproterenol- and acetylcholine-induced nitric oxide formation. METHODS: Isoproterenol-induced relaxations of rat aortic rings with and without endothelia were examined in the absence and presence of halothane. Studies were also done in the presence of inhibitors of nitric oxide-synthase, adenylyl cyclase, calmodulin, protein kinase A, and intracellular Ca2+ release mechanism. The relaxations under some of these conditions were compared with those induced by acetylcholine. Cyclic nucleotide contents of the rings were also measured. RESULTS: Isoproterenol relaxed aortic rings via the endothelium-dependent nitric oxide-cyclic GMP mechanism. Inhibition of adenylyl cyclase or of protein kinase A attenuated the isoproterenol-induced relaxations significantly but did not affect those induced by acetylcholine. Inhibition of intracellular Ca2+ release abolished the acetylcholine-induced relaxations but did not affect those induced by isoproterenol. Calmodulin inhibition attenuated both agonist-induced relaxations significantly. Unlike acetylcholine-induced relaxation, that induced by isoproterenol was not affected by halothane. Isoproterenol increased both the cyclic adenosine monophosphate and cGMP contents of rings significantly when endothelia were intact. Inhibition of nitric oxide synthase attenuated the isoproterenol-induced cGMP content increases significantly but did not affect the cyclic adenosine monophosphate content increases. Halothane (2%) did not affect isoproterenol-induced increases in nucleotide content. CONCLUSIONS: Isoproterenol-induced nitric oxide formation requires the activation of constitutive nitric oxide synthase, but the Ca2+ release mechanism is not involved in activating this enzyme. Halothane can inhibit the nitric oxide-cyclic GMP mechanism only when Ca2+ release is greatly involved in the activation of constitutive nitric oxide synthase.

Acetylcholine↗